Sleeping doesn't seem like it should be all that hard. After all, humans have been sleeping for hundreds of thousands of years -- it's not like flying a plane or performing laparoscopic surgery. Sleeping is high up there on the list of activities essential for survival, along with eating and breathing. And yet, chances are, when it comes to sleep, we're still doing something wrong.

Whether it's falling asleep with the TV on, letting Fido curl up in bed with you or pouring another cup of coffee too late in the day, a lot of what we believe to be acceptable bedtime behavior is simply not. In the slideshow below, we've rounded up 12 of the most commonly-believed sleep myths, and asked the experts to shed some light on the truth.